Flap synchronizing control means

ABSTRACT

A nozzle arrangement is shown having an actuation device at the rear end of flaps which are pivoted intermediate their ends thereof and synchronizing means adjacent the forward ends of the pivoted flaps. The actuating means are shown in detail in U.S. Pat. No. 3,730,436 and the forward synchronizing means comprises engaging male and female members which maintain the nozzle in &#39;&#39;&#39;&#39;round&#39;&#39;&#39;&#39; and are located forward of the pivot point of the flaps so that the male and female members will have their maximum engagement and therefore maximum rigidity at the maximum throat area of the nozzle, said throat area being directly proportional to the position of the rear ends of the flaps. This invention herein described was made in the course of or under a contract with the Department of the Air Force.

United States Patent 1191 Anders et al.

[ 1 June 28, 1974 1 FLAP SYNCHRONIZING CONTROL MEANS [75] Inventors: Larry E. Anders, Palm Springs; .loel

F. Sutton, Lake Park, both of Fla [73] Assignee: United Aircraft Corporation, East Hartford, Conn.

22 Filed: Aug. 29, 1973 21 Appl. No.2 392,834

52 us. 01. 239/265.39, 60/242 51 1111.0. ..B64c15/08 [58] Field of Search..... 239/265.33, 265.37, 265.39, 239/265.41; 60/242 [56] References Cited UNITED STATES PATENTS 3,730,436 5/1973 Madden ct al 239/2653) 3,767,120 10/1973 Harmon 239/2653) Primary Examiner-M. Henson Wood, Jr. Assistant Examiner-Michael Y. Mar Attorney, Agent, or Firm-Jack N. McCarthy 57] ABSTRACT A nozzle arrangement is shown having an actuation device at the rear end of flaps which are pivoted intermediate their ends thereof and synchronizing means adjacent the forward ends of the pivoted flaps. The actuating means are shown in detail in US. Pat. No. 3,730,436 and the forward synchronizing means comprises engaging male and female members which maintain the nozzle in round" and are located for ward of the pivot point of the flaps so that the male and female members will have their maximum engagement and therefore maximum rigidity at the maximum throat area of the nozzle, said throat area being directly proportional to the position of the rear ends of the flaps.

This invention herein described was made in the course of or under a contract with the Department of the Air Force.

9 filaims, 9 Drawing Figures FLAP SYNCHRONIZING CONTROL MEANS BACKGROUND OF THE INVENTION This invention relates to support and control means for variable area nozzles for turbojet engines and while many control means are shown in the prior art, none appear to provide a synchronizing hoop arrangement located forward of the pivot point of the flaps to provide for maintaining the nozzle in round comprising a telescoping type hoop system such that as the nozzle opens to increase the throat area, the hoop system is decreasing in diameter thereby providing maximum en gagement of the male and female telescoping hoop members. A variable area nozzle is shown in U.S. Pat. No. 2,815,643. Another patent and patent applications concerning the type nozzle shown in this application are referred to below.

SUMMARY OF THE INVENTION In a nozzle having convergent flaps which become more difficult to actuate and synchronize at larger and maximum nozzle throat areas, additional synchronizing means must be used and have its maximum hoop rigidity at the large openings including maximum throat area.

A primary object of this invention is to provide a flap synchronizing means including a telescoping type hoop system, including engaging male and female members between adjacent flaps, located forwardly of the primary support pivot such that as the nozzle opens the hoop system is decreasing in diameter thereby providing maximum engagement of the male and female telescoping hoop members.

A further object of this invention is to provide an in terlocking synchronizing hoop system wherein the effectiveness is directly a function of the amount of clearance between male and female members.

Another object of this invention is to support flaps of a nozzle in round" against asymmetrical flow field pressure effects which occur on the nozzle. These effects can occur in a nozzle by forces on connecting external flaps.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a view illustrating the flaps of a nozzle for a turbojet engine on which the invention is used.

FIG. 2 is an enlarged view taken along the line 2-2 of FIG. 1.

FIG. 3 is an enlarged view taken of the forward portion of the main flap shown in FIG. 1.

FIG. 4 is a view taken in the direction 4 on FIG. 2.

FIG. 5 is a view taken along the line 5-5 of FIG. 1 showing the invention.

FIG. 6 is a view taken in the direction 6 on FIG. 5.

FIG. 7 is a view taken along the line 7--7 of FIG. 6.

FIG. 8 is a view taken in the direction 8 on FIG. 5.

FIG. 9 is a view taken of the male engaging member.

DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. I a nozzle system including main flaps 30, balance flaps 50, divergent flaps 60 and external flaps is shown mounted on housing structure 12 of a conventional jet engine 2 comprising a compressor section, burner section, turbine section. exhaust duct and nozzle I0. This basic arrangement including the engine is shown in U.S. Pat. No. 3,730,436.

A plurality of main flaps 30 are mounted for pivotal movement at the rear of the outer housing structure 12. Each flap 30 is formed having a honeycomb interior 29 covered by metal plates welded or brazed thereto. These flaps are each pivotally mounted between two bracket members 32 which extends inwardly from the end of the structure 12. Each flap 30 is pivotally mounted approximately one-third of the distance from its forward edge. Each main flap 30 has an actuating device 33 mounted thereon near the rear edge which is connected to each adjacent flap so that when all of the actuating devices 33 are moved, all of the main flaps are actuated in synchronization. In a construction built, 15 main flaps 30 were used and the connections from the actuating devices 33 extended from flap to flap around the entire circumference thereof providing a variable hoop arrangement.

So that all of the devices 33 and therefore the main flaps are actuated in unison, a unison ring 36 is provided which is connected to each actuating device 33 by an actuating link 38. A plurality of actuating cylinder and piston units are mounted in the housing structure l2 and connected by actuating rods 39 to the uni son ring 36. The unison ring 36 is centered within and slides on track members 37.

A plurality of balance flaps 50 extend forwardly of the main flaps 30. Each flap 50 has its rearward end pivotally connected to the forward end of a main flap 30 while its forward end is mounted for axial movement within the housing structure 12.

A plurality of divergent flaps 60 extend rearwardly of the main flaps 30. Each flap 60 has its forward end pivotally connected to the rearward end of a cooperating flap 30 while its rearward end is pivotally connected to the rear end of an external flap 70. Each external flap 70 has its forward end pivotally mounted at the rear end of housing structure 12, just rearwardly of the bracket members 32.

A nozzle system such as shown in this application, is disclosed in co-pending application Ser. No. 309,567, filed Nov. 24, 1972, for BALANCED FLAP CON- VERGING/DIVERGING NOZZLE to Craig E. Swavely, et al. Further, an exit area schedule selector system for a nozzle such as disclosed herein is disclosed in co-pending application Ser. No. 209,803, filed Dec. 20, 1971 now U.S. Pat. No. 3,767,120, for EXIT AREA SCHEDULE SELECTOR SYSTEM by Kenneth E. Harmon. A seal means for a nozzle such as disclosed herein is set forth in co-pending application Ser. No. 210,017, filed Dec. 20, 1971, for SEAL CEN- TERING AND RETENTION MIEANS by Connie W. McMath.

To properly position the main flaps 30 around the housing structure 12, the bracket members 32 are connected to two annular flanges 34 and 35 which are in turn fixed to the structure 12. This fixedly positions the base portions of each of the bracket members 32. However, to control the sideward movement of the top of the bracket members 32 adjacent their pivotal connection 40 to a cooperating main flap 30, the members are connected by cooperating projecting lugs 42 which extend outwardly and have their ends positioned together and fixed by a pin means 44 placed in aligned openings in the ends of the lugs 42. The connected bracket members 32 permit the main flaps 30 to be positively positioned and maintained in position during operation within close limits. This positioning prevents variance in differential side loads being placed on the brackets 32 from the main flaps 30 such as when no adjacent bracket support is given,

To provide an aid for the synchronization of the main flaps 30 especially when they are at large or near maximum nozzle throat area positions, supporting and synchronizing means 20 is provided ahead of the pivotal connections 40 of the main flaps 30. The supporting and synchronizing means 20 are located on the forward end of the main flaps 30 so that as the nozzle is actuated providing larger throat openings it becomes more rigid, thereby making the hoop formed the most rigid where maximum rigidity is desired.

The supporting and synchronizing means 20 is located between each of the adjacent main flaps 30 and comprises two main parts l a male beam structure 22 and (2) a female guide structure 24. The main beam structure 22 comprises a bracket member 26 fixed to one side of each of the main flaps 30. Bracket member 26 is formed having mounting pads 52 which are fixed as by welding to the side plate 54 of main flap 30 and mounting pads 56 which are fixed to the bottom plate 58 of the main flap 30. To strengthen the connection of the pads 56 to the plate 58 of the flap 30, shear pins 62 are used to provide additional rigidity and prevent a shear failure. The pins 62 are welded to the upper plate 64 of the flap 30 and extend through holes in the lower plate 58 of the flap and are welded to the pads 56.

The structure 22 comprises a bifurcated portion 66 to which a male engaging member 68 is fixed. The male engaging member 68 has a flat portion 72 having two openings 74 therein. In operation the male engaging member 68 has the flat portion 72 fixedly positioned between the bifurcated portion of the bracket member 26. The openings 74 are aligned with openings in the bifurcated portion 66. Pin means are used to fixedly position the member 68 to the bracket member 26. A

male beam 76 projects from the flat portion 72 at a predetermined angle towards the female guide structure on the side of the adjacent flap 30.

The female guide structure 24 includes side bracket means 80 and a bottom bracket means 82 which support a channel member 84 which is fixed to receive the male beam 76 in a manner having a predetermined clearance to be hereinafter discussed. The side bracket means 80 comprises a supporting means which is welded to the sides of the channel member 84 and the side plate 86 of the flap 30. The bottom bracket means 82 is fixed to the bottom plate 58 of the flap 30, including the use of four of the shear pins 62, and fixed to the channel member 84. The female channel 84 projects from the bracket means 80 and 82 at a predetermined angle towards the male beam 46 on the side of the adjacent flap 30, to provide the proper engaging contact therewith. As shown in FIG. the male pin 76 and the channel 84 are positioned at equal angles of approximately 78 to their respective flaps and these angles were used in a construction built having l5 flaps.

in a nozzle construction of this type which was built, the clearance, or gap, at C and D was made having a minimum opening of 0.010 inch. The relative movement of adjacent flaps at the throat is directly proportional to the clearance on each side of the male beam 76 and the female channel member 84. This gap is con trolled to prevent an undesireable out-of-round condition and can also be controlled to prevent the flaps from contacting any of the nozzle actuating means or other parts of the nozzle.

in the construction built, which was referred to above, the male beam 76 and the female channel member 84 extended about 2 inches beyond the edges of the flaps. in operation, when the flaps 30 are in a position of maximum throat area the members 76 and 84 are en gaged for approximately one and one-half inches and when the flaps are in a position of minimum throat area the members 76 and 84 are engaged for approximately 0.7 inch.

We claim:

11. In combination in an engine, an exhaust nozzle mounted thereon, said nozzle comprising a circumfer- I ential row of pivotally mounted main flaps, each flap having an inner and outer surface, each flap having forward and rearward ends, each flap having sides, said inner surfaces forming an inner surface of said nozzle 1 for controlling flow therethrough, actuating means for each of said main flaps, means pivotally mounting each flap between its forward and rearward ends, said actuating means being connected to said main flaps rearwardly of said pivotal mounting means, synchronizing means being connected to said main flaps forwardly of said pivotal mounting means, said synchronizing means comprising telescoping means located between adjacent sides of adjacent main flaps, said telescoping means comprising a male member projecting from the side of one flap having engagement with a female member projecting from the side of the adjacent flap.

2. A combination as set forth in claim )1 wherein each main flap is mounted between two inwardly extending bracket members, adjacent bracket members of adjacent flaps being connected by projections to prevent bending of the bracket members.

3. A combination as set forth in claim 1 wherein said male member is connected to a bracket fixed to the side and outer surface of the flap.

4. A combination as set forth in claim 3 wherein part of the bracket fixed to the outer surface of the flap is fixed to a pin which extends through and is fixed to the flap to support the bracket in shear.

5. A combination as set forth in claim 3 wherein said male member is removably fixed to its bracket.

6. A combination as set forth in claim 1 wherein the male member has a clearance of 0.020 inches in the female member in the transverse plane of the flap.

7. A combination as set forth in claim 1 wherein the male member and female member are positioned so that in operation the engagement varies between its greatest engagement at nozzle open position and its least engagement at nozzle closed position.

8. A combination as set forth in claim 7 wherein the least engagement of the male member and female member is approximately half of the greatest engagement.

9. A combination as set forth in claim 8 wherein the greatest engagement is approximately one and one-half inches and the least engagement is approximately 0.7 

1. In combination in an engine, an exhaust nozzle mounted thereon, said nozzle comprising a circumferential row of pivotally mountEd main flaps, each flap having an inner and outer surface, each flap having forward and rearward ends, each flap having sides, said inner surfaces forming an inner surface of said nozzle for controlling flow therethrough, actuating means for each of said main flaps, means pivotally mounting each flap between its forward and rearward ends, said actuating means being connected to said main flaps rearwardly of said pivotal mounting means, synchronizing means being connected to said main flaps forwardly of said pivotal mounting means, said synchronizing means comprising telescoping means located between adjacent sides of adjacent main flaps, said telescoping means comprising a male member projecting from the side of one flap having engagement with a female member projecting from the side of the adjacent flap.
 2. A combination as set forth in claim 1 wherein each main flap is mounted between two inwardly extending bracket members, adjacent bracket members of adjacent flaps being connected by projections to prevent bending of the bracket members.
 3. A combination as set forth in claim 1 wherein said male member is connected to a bracket fixed to the side and outer surface of the flap.
 4. A combination as set forth in claim 3 wherein part of the bracket fixed to the outer surface of the flap is fixed to a pin which extends through and is fixed to the flap to support the bracket in shear.
 5. A combination as set forth in claim 3 wherein said male member is removably fixed to its bracket.
 6. A combination as set forth in claim 1 wherein the male member has a clearance of 0.020 inches in the female member in the transverse plane of the flap.
 7. A combination as set forth in claim 1 wherein the male member and female member are positioned so that in operation the engagement varies between its greatest engagement at nozzle open position and its least engagement at nozzle closed position.
 8. A combination as set forth in claim 7 wherein the least engagement of the male member and female member is approximately half of the greatest engagement.
 9. A combination as set forth in claim 8 wherein the greatest engagement is approximately one and one-half inches and the least engagement is approximately 0.7 of an inch. 